Interconnecting telephone system.



No. 789,350. PATENTBD MAY 9, 1905. A. K. ANDRIANO.

vINTERCONNEG'IING TELEPHONE SYSTEM. APPLIGATION ULEB M316. 1904.

z SHEETS-SHEET 1.

No. 789.350. PATENTE) MAY 9, 1905. A. K. ANDRIANO.

INTERCONNETING TELEPHONE SYSTEM.

APPLICATION FILED PEB.18. 1904.

2 SHEETS-SHEET 2.

:i l I No. 789,350. Patented May 9, 19,05.

"lhviirnio @raras artnr irrita ALBERT KOCH ANDRIANO, OF SAN FRANCISCO,CALIFORNA, ASSIGNOR TO DIRECT-LINE GENERAL TELEPHONE COMPANY, OF SANFRANClSCO,

ALIFORNIA, A CORPORATION.

lNTERCONNEC-TING TELEPHONIE SYSTEM.

SPECIFICATI'ON forming part of Letters Patent No. 789,350, dated May 9,1905.

Application filed February 18,1904. Serial No. 194,186.

TQ HW N71/07H 'if '/71//1/7/ (W/'l/Wr'l/i/-' naling and talking withoutinterference or Be it known that I, ALBERT Koen' ANniiidisturbancebetween one circuit and ai'iother. 5o ANO, a citizen of the UnitedStates, residing A further and important object of the inat SanFrancisco, in the county of San Franvention is to economize the batteryforce and cisco and State of California, have invented to utilize thebatteries for signaling as well as new and useful improvements inlnterconfor talking purposes, thereby greatly simpli- `necting TelephoneSystems, of which the folfying the construction and reducing the cost 55 lowing is a speciiication. of setting up and supervising a largenumber 'l his invention relates to improvements in of lines. iotelephone systems wherein each station is A further ol'ipict of theinvention is to preprovided with a switching and a signaling vent wasteof battery in case the receiver means that enable it to connect with andmay be left o'llI the hook instead of being 60 call up for communicationany other station hung up after use. not in use at the time. These and.other objects incidental to the In a system containing a small number ofpresent system l attain and secure in and by stations arranged on theinterconnecting means of the construction and arrangements plan, as itis generally termed, and where the of apparatus as herein shown anddescribed. service on such a system is comparatively Figure l is adiagram illustrating the cirlight there is found to be little or nointerfercuits for talking between stations numbered 2o ence between thetalkiiig-circuits completed 1. and 7 when the switches are set forconand in operation between several sets or necting one with the other,the intermediate pairs of stations at the same moment; but in stationsnot being represented. Fig. 2 is a 70 a system involving a considerablenumber of diagram illustrating the sign aling-circuits bestations thatare in operation at the same tween the same stations when station No. 1

25 time, and especially where the same retuinis calling No. 7. Severalof the intermediate wire is combined or connected at the same stationsare represented in this diagram. moment with two or more directline-wires Fig is afront view of one of the localswitclito formdi'llerent metallic circuits for several boxes containing the switchingmechanism, pairs of telephones or stations, it has been the circuitmaking and breaking eom'iections 3o found that the talking-circuitssometimes incontrolled by the telephone-hook, and other terl'ere withand set up such inductive condicomiections, the front of the box beingretions on the lines as to causo the talking on moved. Fig. L.l is acentralverticalsectional SO one circuit to be heard on another circuit.ln view through part of the mechanism shown addition to thisobjectionable feature the in Fig. 3. Fig. is a simplilied diagrammatic35 signaling-circuits over which one station. calls view illustratingthe manner in which by up another are also liable to affect thetalkvarying con'ibinations of conductors [ifteen intr takingplace onother lines at the moment separate metallic circuits may be obtained olsignaling by causing the pulsations of the with six coni'luctors, thehome contacts only current on the signaling-circuit to act on the ofboth the direct and the return conductors 40 talking-circuits then. inuse. being indicated.

My present invention has for its object to In the following descriptionthe terms diprovide a system of metallic circuits for talk* rectconductor am return-conductor are 9o ing and signaling that shall befree from the used arbitrarily to designate the two sides ofabove-mentioned defects and objectionable the circuit that unite twoconnected sta- .i 5 features and by means of which also a contions; butit will be understood that the lines siderable number of stations may beconprimarily used as direct conductors in one nected in one system, witha capacity for setset or group of circuits illustrated in the diating upa number of metallic circuits for siggrams may be simultaneously used asreturnconductors for other circuits, this fact being l illustrated byFig.

The grouping of the stations in the manner illustrated in this case andthe connecting of them by direct and return conductors and the means forselecting one wire for use as a direct conductor and another for use asa return-conductor, so that acircuit so completed for use becomesindividual to the particular connected stations, are not herein claimed,but are the subject of claims in anotherapplication liled by myself andHermann Herbstritt, November 21, 190.3, and serially numbered 182,092.

The invention that forms the subject-inatter of the present case isshown as applied to an interconnected system,forwhich it is particularlywell adapted, and when so applied each station is provided withswitching devices by means of which a metallic circuit may be completedbetween that one and any other selected station of the system. As shownin the drawings, the selecting devices by which one station is connectedwith another are preferably divided into two sets, one controlling theconnection of the local station with the direct line conductors andherein designated, for the purposes of description,as thedirect-lineswitch and the other controlling the connection with thereturnconductors, this being herein designated the return-lineswitch.HThe direct-line switch consists of a set of stationary contacts orpoints c, constituting the terminals of the direct line-wires that enterthe station, and a movable contact or switcharm for making contact withsuch stationary contacts, one side of the local circuit of the stationbeing connected with the said movable contact, while the return-lineswitch consists of a set of stationary contacts or points e,constituting the terminals of the return-conductors that enter thestation, and a movable contact or switch-arm d for making contact withthese stationary contacts, the other side of the local circuit beingconnected with the movable contact d. These two arms or movable contactsb and d may be and preferably are so mounted as to turn about a commonaxis, as indicated in Fig. 4, and are normally maintained upon certainof the stationary contacts, commonly called the f home contacts. Spiralsprings s and tare employed to automatically return them to normalpositions of rest, as is customary in apparatus of the kind to whichmine belongs. The movable contacts have connected with themratchet-wheels m and n, with which coperate detents 7) px for lockingthe movable contacts upon the stationary contacts, to which they may beset until they are released upon the hanging of thetelephone-receiverf11 upon the hookj'. The telephone-hook or arm]l isprovided with a tripping-arm .2, mounted in a suitable support fc andextending between studs y, carried by an arm w, that operates to throwofll the detents when the telephone is` hung up. Further description ofthese parts is not necessary, as they form no part of the presentinvention and may be of any usual or approved character.

Referring now to the diagrammatic views, Figs. 1 and 2, wherein mypresent invention is illustrated, 1, 2, 3, 4, 5, and 6 designate theconductors interconnecting the stations. Any of these may be used bothas a returnconductor for one station and as a direct conductor foranother, as indicated in Fig. 5. Those wires or conductors thatterminate at the points or contacts c of the station are the directconductors for that particular station, while those that terminate atthe contacts c are the return-conductors, though, as already indicated,the terms direct and return are herein used arbitrarily to facilitatedescription of the system. The essential features of a localtalking-circuit are represented in these views, and l have chosen, forthe sake of illustration, an arrangement in which the receiver r is in aclosed circuit containing the secondary winding of the induction-coil.Starting from the movable contact or switcharm b of the direct-lineswitching or selecting device with which one lead of the local circuitis connected, that circuit when connected up for talking may be tracedas follows: the switch-arm b, the conductor 8, uniting the switch-armwith the telephonehook j, the contact 13, with which the telephone-hookengages when the receiver is taken down, the wire or conductor 17, thetransmitter t, the primary winding S of the induction-coil, theconductor 16, leading to the front stop 15 of the ringing-key g, themovable member of the ringing-key, and the conductor 20, uniting thelatter with the switch-arm d of the return-line switch. It will thus beseen that the two switches, which when connected as described constitutethe two terminals of the local circuit, make it possible to connect thelocal circuit y with any of the lines that enter the station andterminate at the contacts c and e and through these lines or conductorswith any of the other stations. The complete talkingcircuit between twoconnected stations is indicated in this view by the heavy line and maybe furtherl traced as follows, beginning with the stationary contact towhich the movable contact d has been set: the wire 18, uniting the saidstationary contact with that conductor 6 which is individual to or acommon conductor for the connected station No. 7, the conductor 6, thewire 18 at station No. 7, uniting the conductor 6 with the home contactof the return-line switch, the arm d of that switch, the conductor 20,the movable member of the ringing-key, the front stop 15, the conductor16, the primary winding s, the transmitter, the conductor 17, thecontact 13,

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with which the telephone-hook engages when the receiver is taken down,Athe telephonehook the conductor 8, the movable contact b el thedirect-line switch that is resting 5 on its home contact, the wire thatunites this contact with the direct conductor that is individual tostation No. 7, the battery (L, the conductor l., and the wire unitingthis conductor with that stationary contact at staio tion No. 1 that isindividual to station No. 7 and to which the switch-arm b has been.moved and 'from which the tracing o'l the talking-circuit began. Theelectrical energy for operating this circuit is obtained from the i 5battery a, which, it should be observed, is directly upon the line. Itis located outside the local circuit of' the station and in one of thelines er conductors terminating, respectively, at the home contacts cand c of the zo called-up station, preferably in the line that goes tothe direct-line switch. The advantages of this arrangement are apparent,as thereby battery force directly on. the line may be obtained, providedthe movable con- 2 5 tacts o'l the switches oi the called-up station areon their home contacts, as they should be except when that station isitsehc making connection with another station, no matter what otherstation in the system may be cen- 3o nected therewith.

The ringing-circuit is indicated in Fig. 2, wherein station No. l isrepresented as calling up station No. 7. Referring to this view, thecalling-circuit may be traced as follows,

3 5 starting with the movable contact b at station No. l: the switch-arml), the conductor 8, the back stop 14 of the ringing-key g, the movablemember oi the latter, which when pressed engages with such back stop,the

4o conductor 20, the switch-arm d, which has been adjusted to thatcontact c oi the return.line switch that is individual to the stationbeing called up, in this instance station No. 7, the wire 18, theconductor 6, the wire 4 5 10, the bell 7L of station No. 7, the wire Q,the contact l2, upon which the telephone-hook j'rests when the receiver'is hung up, the telephbne-hookj, the conductor 8, thc movable contact bof the direct-line switch now rest- 5o ing upon its home contact c, thebattery a, and the direct line conductor l, to back the movable contactat station No. l, this circuit being indicated by the dotted line.llVhen this circuit is thus completed, the bell 5 5 at station No. 7will ring so long the pushbutton is pressed or until one or both the receivers are removed, thus breaking the circuits at contactsf-lZ.

The electrical force 'for operating the call- 6o nig-circuit is obtainedtrom the battery c,

which, as has already been stated when. describing the talking-circuit,is on the line outside the local circuit and is on the line individualto the called-up station, so as to be o5 always ready 'for use in makinga call when the station is not busy. This disposition and arrangement ofbattery permits the system to be operated without a common ringingbattery and circuit and makes it possible to utilize the saine batteryboth for calling and 'for talking purposes.

It will be seen by reference to the diagrams that in each line orconductor individual to a station there is a battery that serves tooperate the instruments in that station whenever it is called, but thatwhenever a call is sent from such station the connection with suchbattery is broken .in the act of making connection with the distantstation. It will be observed that each battery is connected into theline in the same manner as each other battery-that is to say, if thepositive pole of one battery be toward the home contacts c of the lineindividual to that station then each other battery will have itspositive pole disposed in the same relation to the homecontact of thestation the .instruments of which it serves to operate. rl`hisdisposition oi" the batteries renders it impossible for the current fromany battery to nd a circuit through a loop including a bell of a stationother than the one intended to be falled, which might otherwise takeplace should a strong battery be employed for ringing purposes. lf thecircuits be traced in the present case, it will be seen that whenever aloop is `formed other than the one intentionally made by the act ol"connecting two stations it will include two of the batteries a, andthese batteries will have like poles connected together, thus opposingone another and preventing a illow of current or so retarding the low ofcurrent as to render it ineffectual for operating bell or other callinginstrument.

lhat l claim as my invention, and desire to secure by Letters Patent,isY

1. In a telephone system the combination with a station, oiE a pluralityot other stations connected therewith by conductors individual to suchother stations and terminating at contacts at the Iirst-named station,means for completing an electrical circuit between any station of thesystem and the Alirst-nanied station, means at the lirst-named stationlor selecting the conductor individual to any other station andcompleting a circuit therewith over such. conductor, and a source ofelectrical energy in the conductor individual to a station situatedoutside the selecting means ol" the station.

2. In a telephone system the combination et a plurality ol stationsconnected with each other by direct line conductors and switchingdevices, and a source el" electrical energy in. the direct lineconductor ol" each station situated outside the switching device ot thestation.

3. ln a telephone system, the combination oiE stations (.:onnectcd bydirect line conductors having terminals at the stations, a movlOO AIO

able conductor at each station connected with one side of the localcircuit of that station and arranged to normally connect with the lineindividual to that station, or by adjustment to connect with the line ofany other station, a source et electrical energy in each direct lineconductor situated outside the movable conductor of its station, and areturn-conductor with which the opposite side of each local circuit isconnected.

et. ln a telephone system, the combination of a plurality of stationsconnected through switching devices and line conductors having terminalsat the stations, a movable conductor 'for connecting one side of thelocal circuit at a station with the line conductor individual to thestation and also by adjustment for connecting it with the line conductorot' any other station, a return-conductor for completing the circuitwith which the opposite side ot each local circuit is connected, and asource of electrical energy for each completed circuit arranged outsidethe local circuit of the station, the connection with such source ofenergy being maintained while the movable contact is in connection withthe line individual to its station and broken when moved to the lineindividual to any other station.

5. In a telephone system, the combination of a plurality of stationsconnected with each other by direct line conductors and switchingdevices, and a battery in the direct iine conductor of each stationsituated outside the switching device of the station, the said batteriesbeing similarly disposed with reference to the lines in which they arelocated.

6. In a telephone system, a pluralitJ of stations connected throughswitching devices and direct line conductors having terminals at everyswitch, a source of current in every direct line conductor arrangedoutside the switching device, a local circuit at every station, meansfor normally connecting one side of the local circuit with a direct lineconductor individual to the station, and also by adjustment forconnecting it with the direct line conductor of another station, areturnconductor to which the circuit of the station is connected on itsopposite side, and a circuit-closer in the local circuit arranged tounite the terminals of the local circuit and cut out the localinstruments.

7. In a telephone system, stations interconnected through individualswitching devices and metallic circuits, each composed of a directconductor and a return-conductor, a local circuit at each station and asource of current in every direct conductor arranged outside theswitching device, the latter operating to connect one side of the localcircuit normally with the source of current, or by adjustment to cutoutthe source of current and connect the local circuit directly with theline of another station.

8. In a telephone system, a plurality of stations each having a localcircuit, direct line conductors between the stations terminating atcontacts individual to the several stations, a switching deviceconnected with the local circuit and arranged to make connection withany of the direct-line contacts, a batterysituated in eachdirect lineand connected on one side with the home contact oi its line, areturn-conductor common to the station, and means for connecting thelocalA circuit with the said return-conductor.

Q. ln a telephone system, a plurality of stations interconnected throughdirect line conductors and individual switching devices, a local circuitat cach station, a battery in cach line individual to a station, andmeans at each station for normally connecting the local circuit with thedirect line individual to that station and with the battery in suchline, and adapted by adjustment to cut out the said battery and connectthe local circuit with the corresponding battery in another line.

10. In a telephone system, a plurality of interconnectible stations, anelectrically@ actuated signaling device at each station, switchingdevices adapted to connect the signaling device of the station at willwith either the signaling or the talking circuit of another selectedstation, and a source of electrical energy in the direct line conductorof every station situated outside the switching device ol the station.

ln testimony whereoie l have hereunto set my name to this specificationin the prcse'iice of two subscribing witnesses.

ALBERT KOCH ANDRIANO.

Vitnesses:

JOHN S. PARTRIDGE, M. REGNER.

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